It is well known in the art that an electric motor and a motor drive for the motor can be utilized to move a guide means used for a sorter or other similar device. Although an electric motor, such as a stepper motor, whose rotation can be accurately controlled, is available, such a motor not only has relatively low torque, but is also costly. In contrast, a DC electric motor is less costly and superior in its starting characteristic. In view of this fact, there has always been a serious demand for use of the DC electric motor to achieve the abovementioned purpose.